1. Department of Medicine; Groote Schuur Hospital and University of Cape Town; Cape Town South Africa
2. Department of Public Health; Faculty of Medicine and Biomedical Sciences; University of Yaoundé 1; Yaoundé Cameroon
3. Department of Internal Medicine and sub-Specialties; Faculty of Medicine and Biomedical Sciences; University of Yaoundé 1; Yaoundé Cameroon
4. Department of Epidemiology and Public Health; Centre Pasteur of Cameroon; Yaoundé Cameroon
5. Faculty of Medicine; University of Paris Sud XI; Le Kremlin-Bicêtre France